Television system



Jam 1935 V G. SCHUBERT 2,026,915

TELEVISION SYSTEM Filed July 28, 1932 In venzor:

Patented Jan. 7, 1936 TELEVISION SYSTEM Georg Schubert, Berlin, Germany, assignor to the firm of Fernseh Aktien-Gesellschaft, Zehlendorf, near Berlin, Germany Application July 28, 1932, Serial No. 625,452

. In Germany July 30, 1931 4 Claims.

This invention relates to television systems, and more particularly to an arrangement of the kind described in the U. S. application Ser. No. 606,471.

In the United States application in question there is described a connection system in which the luminous tube is connected in series with the output tube of the low-frequency amplifier and a resistance, and is traversed in direct fashion by the emissive current of the output tube. As shown in Fig. 1, the resistance is preferably bridged by a capacity. Since the luminous tube having a positive column possesses a negative characteristic, the same in conjunction with the series-connected resistance and the capacity connected in parallel readily tends towards oscillation.

According now to the invention, this may be avoided if a portion of the entire resistance is bridged by the condenser shown, so that the oscillations are damped by the part of the resistance which is not bridged, and steady conditions are ensured. If necessary, the bridging condenser should be omitted entirely, and a pure ohmic resistance employed, a condition which certainly would not occur very frequently. Owing to the increased damping on account of the connected resistance greater amplification is certainly required in order to control the luminous tube; however, this disadvantage must be accepted in view of the steady and satisfactory conditions obtained.

What I claim as new and desire to secure by Letters Patent is:

1. In a television system, a luminous tube having a positive column, a low frequency amplifier having an output tube,.a source of direct current in the anode circuit of said output tube, aresistance in series with said luminous tube in said anode circuit, and a condenser shunted across said source of direct current and a part of the said resistance.

2. In a television system, the combination of a low-frequency amplifier having an output valve,

a resistance and a positive-column luminous tube 5 having a descending characteristic of current and voltage connected in series with said resistance in the anode circuit of said output valve, a source of direct current in said anode circuit, and a condenser shunted across said source of direct cur- 10 rent and a part of said resistance, whereby that 7 part of the resistance not shunted by said condenser is adapted to damp commencing oscillations.

3. In a television system, the combination of a i5 low-frequency amplifier having an output valve,

a resistance and a positive-column luminous tube having a descending characteristic of current and voltage connected in series with one another in the anode circuit of said output valve, and a 20 condenser having one of its electrodes connected with the filament circuit of the output valve and having its other electrode connected to said resistance between the ends thereof, whereby only a portion of said resistance is shunted by said 25 condenser.

4. In a television system, the combination of a low-frequency amplifier having an output valve, a resistance and a positive column luminous tube having a descending characteristic of current and voltage connected in series with said resistance in the anode circuit of said output valve, a source of direct current in said anode circuit, and a condenser shunted across said source of direct current and a portion of said resistance, said condenser being adapted to be connected to diiierent points of said resistance, whereby the remaining unshunted portion of said resistance is efiective to damp commencing oscillations.

GEORG SCHUBER'DI'. 

